According to Max Schrems, front man of the Europe-v-Facebook group and plaintiff in the Irish case, this data is not adequately protected when Facebook and other U.S. tech companies take the data of EU citizens to the U.S. for processing. Personal data processed in the U.S. can be accessed by the U.S. National Security Agency (NSA) for mass surveillance purposes, and by giving the NSA access to it fundamental EU privacy laws are violated, he said.

The case that is now before the CJEU started when Schrems filed a complaint about Facebook’s data processing with the Irish Data Protection Commissioner in 2013. The DPC refused to start an investigation because it found it was absolutely bound by the Safe Harbor requirements. Schrems then challenged this decision with the Irish High Court, which referred the case to the CJEU.

Schrems’ arguments about the NSA’s spying may have swayed the Irish High Court, which said in referring the case: “There is, perhaps, much to be said for the argument that the Safe Harbor Regime has been overtaken by events. The Snowden revelations may be thought to have exposed gaping holes in the contemporary U.S. data protection practice.”

He is not allowed to identify the countries due to strict CJEU rules, he said in an email. A CJEU spokesman declined to comment on which parties submitted their views or what their views were.

Despite the strict CJEU rules, Schrems said he could say that several proposals were made to solve the case. One proposal was made to suspend data flows to individual companies like Facebook, Apple, Google, Yahoo or Microsoft by invoking an emergency provision in the Safe Harbor rules.

Waiting for a political compromise between the EU and the U.S. on Safe Harbor was also mentioned, he said. The Commission hopes to conclude negotiations over Safe Harbor by the end of May.

Schrems said he and others asked the court to invalidate the Safe Harbor agreement.

Despite the serious implications of invalidating the Safe Harbor rules, it would not make data exchanges between the EU and U.S. impossible, Schrems said. Self-certified companies might lose their rights but would still be able to apply for data transfers under a number of other legal regimes. Nevertheless, a revocation may make it harder for U.S. companies to retrieve data from the EU and they might be prompted to invest in secure European data centers, he said.

Tuesday’s hearing in Luxembourg will start at 9.30 a.m. CET and will be open to the public. No live stream of the proceedings will be provided or permitted, a spokeswoman said.

The CJEU will take at least five months to make its decision.

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